Floating offshore turbines - installation methods

Abstract

Floating offshore wind turbines are a possible source of large scale electricity. Fabrication and offshore installation design of these large floating structures is required to provide confidence to developers and insurers that they are constructed in a safe and cost effective manner. The design methods developed in this paper cover the substructure types such as Spars, semi submersibles, barges and TLPs. The engineering of mooring types includes catenary, taut and tension, plus turret mooring. This paper details the preparation of engineering requirements for installation vessels and large onshore cranes used for the shipyard construction of substructures for floating wind. Each installation phase, for a floating offshore wind turbine, raises issues regarding existing construction methods and the need to develop revised installation works. The engineering processes include mooring installation and connection. In addition consideration of load-out analysis, ocean transportation analysis including sea-fastening, intact stability and tow motion response. Installation analysis is required for lifting, up-ending, afloat construction, and cable lay methods. Floating offshore wind turbines are offering a new approach to using marine resources and this paper will provide information on how naval engineering can be used to promote this development.